Multistage combustion turbine



March 31, 1931. H. HOLZWARTH MULTISTAGE COMBUSTION TURBINE Original Filed Nov. 2'7, 1928 Invenlor: l/qlvs l/OLZW/IRTH mmkm .ffttorney;

Patented Mar. 31, 1931 UNITED STATES PATENT OFFICE HANS HOLZWARTH, 0F DU'SSELDORF,

GERMAN Y, ASSIGNOR TO HOLZWARTH GAS TUR- BINE 00., OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF DELAWARE MULTISTAGE COMBUSTION TURBINE Application filed November 27, 1928, Serial No. 322,153, and in Germany December 8, 1927. Renewed July 29, 1930.

My invention relates to improvements in multi-stage combustion turbines, and it is an object of the invention to reduce the temperature of the gases exhausting from a higher stage prior to their entry into a lower stage, and to utilize the heat so abstracted to superheat steam which may then be used in any desired manner. Other objects will appear more fully from the following description and the features of novelty will be pointed out in the appended claims.

In the accompanying drawing which shows by way of example an embodiment of the inventive idea without defining its limits, Fig. 1 shows an elevational View of a two stage combustion turbine partly in axial section; while Figs. 2 and 3 illustrate on an enlarged scale details of Fig. 1.

In Fig. 1, I have shown only such parts of a multiple stage combustion turbine as are necessary for a complete understanding of my invention. It will be understood that the turbine includes preferably a plurality of combustion chamber which are charged in timed relation with an explosive mixture of air and fuel, such mixtures being exploded or burned in any suitable way and the re sulting products of combustion, which are of high temperature and pressure, escaping through nozzle valves (not shown) into channels a, from which they are directed by nozzles 6 against double rin s of blades rigidly mounted on the rotatable (gurtis wheel or rotor c of the high pressure stage. Only one channel a and one nozzle 6 are shown on the drawing but it will be understood that a plurality of combustion chambers may be employed, for instance, as disclosed in my Patent N 0. 877,194, preferably symmetrically arranged about the rotor circumference. A circular or annular connecting or collecting chamber Z is located between this high pressure stage of the turbine and the Parsonfs section 03 forming the low pressure stage of the turbine and receives the gases exhausting from the high pressure stage.

In accordance with my invention, the connecting chamber Z is provided with one or more heat exchangers which may be in the form of superheating tubes or coils as shown group f2 at f f through which cooling steam is adapted to flow. The tubes are arranged along and adjacent to the inner and outer walls of the connecting chamber and thus form a tube-lined conduit for the gases. The chamber is also provided along its outer and inner'circular walls with jackets forming the cooling spaces 9 and h, respectively, into which cooling water or oil may beintroduced. The cooling spaces 9 and It are connected with each other by means of one or more equalizing conduits 2'. The superheating tubes may be arranged in two groups, shown at f and f the groups being distributed in the direction of travel of the gases, and the group f being in advance of group f and consequently struck by the combustion gases directly as they leave the high pressure turbine stage. In this way steam of different degrees of superheat may be obtained from the different coils. Each group consists of a set of inner and a set of outer tubes, as shown in Fig. 1. The inner and outer tubes of each group may be connected to each other in series to form a continuous coil, or only the tubes within each set may be connected in this Way, thereby forming an inner and an outer coil, the two coils of each. group in such case being connected in parallel. The several groups of coils of tubing have separate inlets and outlets for steam. Saturated steam is conducted to group f through connection is, and to through connection Z the highly superheated steam being withdrawn through conduit 70 and the less superheated steam through conduit Z Figs. 2 and 3 show on an enlarged scale a particularly advantageous way of connecting the superheated tubes f to each other. The connection is effected by means of sheet metal strips f which are positioned upon the inner side of the inner tubes and upon the outer side of the outer tubes in spaced relation to the adjacent connecting chamber wall and are welded to the tubes along their circumferences. In this. way a complete shell or jacket is formed within which the combustion gases flow. The gases consequently give up their heat directly only to the superheatin'g tubes f whiledirect heating of the cooling conduction to the cooling chambers through the interposed insulating layer of air. An

intense heat is thus transferred to the superheating tubes, where it serves to superheat steam, and only a low degree of heat to the cooling chambers, whereby the most efficient utilization of the heat abstracted from the exhaust gases at this point is afforded.

In the construction shown in Fig. 3 the tube f located close to the rotor c and charged with steam is exactly fitted to the outline of such rotor so that steam flowing through the said tube f' advantageously serves simultaneously to cool the sensitive rotor body. While the turbine housing m itself is composed of a ferrous casting, such as cast steel or cast iron, the housing wall n bordering upon the rotor body surface is composed of an aluminum alloy or other suitable highly heat-conducting alloy in order to effect a further cooling of the rotor body by means of the cooling medium in the cooling space 72..

Variations may be resorted to within the scope of the appended claims without departmg from the spirit of the invention.

I claim:

1. In a multi-stage combustion turbine, the combination of a high pressu e stage adapted to be operatedby combustion gases, a low pressure stage operated by the gases exhausting from such high pressure stage, a connect ing chamber located between said high and low pressure stages and arranged to receive the gases discharged from such high pressure stage prior to their entry into the low pressure stage, jackets surrounding the walls of said connecting chamber, whereby cooling spaces for such chamber are provided which are adapted to be filled with a cooling fluid, a heat exchanger located in said connecting chamber, a conduit for conducting steam to said heat exchanger. and a conduit for withdrawing therefrom the steam which has been superheated by the heat abstracted from the exhaust gases.

2. The construction as claimed in claim 1, wherein said heat exchanger is composed of coils of tubing.

3. In a multi-stage combustion turbine, the combination of a high pressure stage adapted to be operated by combustion gases, alow pressure stage operated by the gases exhausting from such high pressure stage, a connecting chamber located between said high and low pressure stages and arranged 'to receive the gases discharged from such high pressure stage prior to their entryinto the low pres sure stage, jackets surrounding the walls of in said connecting chamber,

said connecting chamber, whereby cooling 4. The construction set forth in claim 3 wherein said heat exchangers are composed of coils of tubing.

- 5. In a multi-stage combustion turbine, the combination of a high pressure stage adapted to be operated by combustion gases, a low pressure stage operated by the gases exhaust; ing from such high pressure stage, a connecting chamber located between said high and low pressure stages and arranged to receive the gases discharged from such high pressure stage prior to their entry into t e low pressure stage, jackets surrounding the walls of said connecting chamber, whereby cooling spaces for such chamber are provided which are adapted to be filled with a cooling fluid, a plurality of heat exchangers located conduits for conducting cooling steam to said heat exchang ers, conduits for withdrawing therefrom steam which has been superheated by the heat abstracted from said gases, and a jacket connected to said heat exchangers, the latter being positioned upon the inner side of sa d jacket exposed to the combustion gases, said jacket being adapted to protect the walls of the connecting chamber from the direct 1nfluence of the combustion gases.

6. The construction set forth in claim 5,

in which the heat exchangers are composed of coils of tubing connected to the acket upon the surfaces thereof which are adjacent to the cooling spaces of the connecting chamber.

7. The construction set forth in claim 5 wherein said heat exchangers are composed of coils of tubing, said jacket being composed of sheetmetal strips welded to said tubes and connecting the same.

8. The construction set forth in claim 1 wherein said heat exchangers are composed of coils of tubing, the parts of said co1ls 1y,- ing closest to the rotor of the hi h pressure stage being fitted to the outline 0 such rotor so as to lie as close as possible to the latter.

9. The construction as set forth in claim 1 wherein the walls of said connecting chamber with the exception of that lying ad] acent to the rotor ofthe high pressure stage are composed of a ferrous casting, the wall lying adjacent to said rotor being composed of a highly heat-conducting aluminum alloy.

10. The construction set forth in claim 1 wherein the walls of said connecting chamber with the exception of that lying ad acent to the rotor of the high pressure stage are composed of a ferrous casting, the wall lying adjacent to said rotor being made of a highly heat-conducting alloy.

11. The construction as set forth in claim 1 wherein said steam superheating device is composed of a plurality of groups of coils distributed in said chamber in the direction of travel of said gases, said groups having separate inlet and outlet conduits, whereby steam of different degrees of superheat may "be obtained.

12. The construction as set forth in claim 1 wherein said steam superheating device comprises a plurality of tubes spaced from the adjacent Wall of thechamber, and a jacket connected to said tubes at the outer sides thereof, said jacket being adapted to protect,

the wall of said chamber from the direct infiuence of the combustion gases. 4

13. The construction as set forth in claim wherein said superheating device is composed of coils of tubing, the parts of said coils lying closest to the rotor of the high pressure stage being fitted to the outline of such rotor so as to lie as close as possible to the latter and exert a cooling influence thereincluding jackets surrounding the walls of 'said connecting chamber, whereby cooling spaces are provided adapted to receive a cooling fluid, said walls with the exception of that lying adjacent to the ro or of thevhigh pressure stage being composed of aferrous casting, the wall lying adjacent to said rotor being composed of a metallic substance.

. v HANS .HOLZWARTYH.

highly heat-conducting l4. The constructionas set forth in claim 1 

